THE future is crystal clear for Waterford's John O'Shea - the Manchester United youngster has an Old Trafford and world stage beckoning.

The Reds' 20-year-old Republic of Ireland defender made an impressive Premiership debut against West Ham last Saturday and continued with another commanding display in the 5-0 defeat of Derby County on Wednesday.

Against Derby O'Shea formed Sir Alex Ferguson's 13th central defensive partnership of the season and the latest link up between the Irishman and Laurent Blanc could get a chance now to form a regular pairing.

With United's defence blighted by medium to long term injuries to Ronny Johnsen, Wes Brown and David May, O'Shea's promising elevation to senior status has delighted Sir Alex Ferguson.

''I have to see what John is capable of because with Wes, David May and Ronny injured I really need back up in that position,'' he said.

''John has done nothing wrong in his two matches and has done very well. We know his promise is very good.''

And former Red and Republic striker Frank Stapleton believes a future as a United regular plus a World Cup opportunity with Mick McCarthy's Irish side in Japan and South Korea is definitely on the agenda for O'Shea.

Defence opening

''Opportunities do not present themselves that often at United but I think there is a real chance at the centre of defence opening up for John,'' said Stapleton.

''I think in a year he should be looking to be established in the defence or seriously fighting for a senior role. He's certainly got a chance.

''The central defensive positions aren't cut and dried at Old Trafford at the moment so there is a real opportunity there. And if it happens for him on a regular basis this season at United then there is no reason why he couldn't make the Republic's World Cup squad.

''The central defensive role for Ireland isn't securely tied down by anyone at the moment either so if John can manage to force his way into Sir Alex Ferguson's side on a more regular basis then I can't see how Mick McCarthy could ignore him for Japan.''

O'Shea has already gained one full Irish cap as a substitute against Croatia this season and he's been an Under-21 regular.

The 20-year-old spent last season in Belgium with United's feeder club Royal Antwerp. He has returned to Old Trafford this season and United's injury and form problems in defence which has seen ten different partnerships used has allowed O'Shea to make a breakthrough.

He has also made substitute appearances against Lille, Liverpool and Arsenal and as well as his first Premiership start against west Ham he played at Highbury in the worthington Cup.